A Firefox release is being pushed— version 66.0.4. This release repairs the certificate chain to re-enable web extensions, themes, search engines, and language packs that had been disabled. There are remaining issues that we are actively working to resolve, but we wanted to get this fix out before Monday to lessen the impact of disabled add-ons before the start of the week.

We’re still preparing the notes for this release, and will post them here when they are ready. Please check back later.

We strive to make Firefox a great experience. Last weekend we failed, and we’re sorry.

An error on our part prevented new add-ons from being installed, and stopped existing add-ons from working. Now that we’ve been able to restore this functionality for the majority of Firefox users, we want to explain a bit about what happened and tell you what comes next.

Add-ons are an important feature of Firefox. They enable you to customize your browser and add valuable functionality to your online experience. We know how important this is, which is why we’ve spent a great deal of time over the past few years coming up with ways to make add-ons safer and more secure. However, because add-ons are so powerful, we’ve also worked hard to build and deploy systems to protect you from malicious add-ons. The problem here was an implementation error in one such system, with the failure mode being that add-ons were disabled. Although we believe that the basic design of our add-ons system is sound, we will be working to refine these systems so similar problems do not occur in the future.

In order to address this issue as quickly as possible, we used our “Studies” system to deploy the initial fix, which requires users to be opted in to Telemetry. Some users who had opted out of Telemetry opted back in, in order to get the initial fix as soon as possible. There is now no longer a need to have Studies on to receive updates anymore. In order to respect our users’ potential intentions as much as possible, based on our current set up, we will be deleting all of our source Telemetry and Studies data for our entire user population.

Shame other companies aren't so upfront and honest with customers when things go wrong.